The invention relates to a supervising arrangement for equipment in a station in the form of a transmission network, the arrangement comprising an alarm system which is responsive to alarm signals occurring in the equipment, different alarm signals from different apparatus being displayed by means of indication lamps for each of the possible alarm signals, and energizing circuits for the indication lamps being controllable by means of a central key with which also, after reception of an alarm signal, the alarm system can be released again for the reception of a subsequent alarm signal.
In a transmission network, alarms which may occur can result in the restoration of the traffic not being effected rapidly, because a fault causing an alarm does not actually occur in the station where the alarm is reported. In order to release the alarm system in the station to enable the detection of new alarms, it must be possible for a subsisting alarm to be suppressed. This can be effected by means of a central key.
Such an arrangement is disclosed in, for example, German Auslegeschrift 1.921.757, in which the indication lamps are arranged in such a way that alarm signal lamps form the abscissa and location indicating lamps form the ordinates of a system of coordinates, the location indicating lamps being controlled via a circuit such that, at the beginning of an alarm condition, the relevant lamps start flashing, while after the central key has been depressed, these lamps remain lit steadily. After the alarm condition has been eliminated, the lamps start flashing again and the lamps go dark after the central key has been depressed.
This prior art supervising arrangement has the drawback that after suppression of an alarm signal the relevant indication lamps remain lit, which consumes much power. In addition, this prior art arrangement has the disadvantage that when several systems give an alarm one after the other, a logging unit is required to check which alarm signal was received last. It is furthermore necessary, after elimination of an alarm condition, to turn-off the then flashing indication lamp by operating the central key. If an unmanned station is concerned, a special visit to the unmanned station is necessary for this purpose.